Father Gabriel Zeis also served as Diocesan Vicar for Catholic Education.

"Although Father Zeis denies the allegation, he has resigned from his positions, effective immediately," according to a statement from the Diocese of Trenton, which said an investigation has been opened by the TOR Franciscan Order into the allegation's credibility.

The Diocese said it has not received any complaints against Zeis, who is known as "Father Gabe" at the Aquinas Institute, the Diocese's mission on the Princeton campus.

In a separate statement, the Franciscans said they had also not received any complaints regarding Zeis during his ten year term as president of Saint Francis University, which is in western Pennsylvania.

"This allegation from 1975 references Fr. Zeis during his time at the seminary," the Franciscans said.

Princeton University in a statement to NJ.com said Zeis was not a university employee and has no role in his resignation.

Aquinas student president Matt Igoe told the Daily Princetonian student newspaper the allegation was a "shock" and the institute has known Zeis as a "kind and generous chaplain." Igoe said the institute will continue its work awaiting a new chaplain.

The Diocese encouraged anyone who has been sexually abused as a minor or vulnerable adult by any representative of the Church to report that abuse to local law enforcement authorities and the Diocese of Trenton by calling their hotline at 1-888-296-2965.